美國著名Carollo 環(huán)境工程公司專家Rod Reardon 展望：污水處理當(dāng)前及未來發(fā)展趨勢
The wastewater industry faces many new challenges that complicate near- and long-term planning decisions. Increasing energy costs, trace organic compounds, finite resources, water conservation, and inexorably more stringent regulations, must all be considered before investing in major facility improvements. While the future is never certain, inclusion of strategic exercises like scenario planning and future mapping during the planning process can help to define the boundaries of what the future might bring to treatment facilities.
Futurists point out that the important trends in the future have their seeds in the present. On this basis, treatment technologies will evolve to address five major trends in wastewater treatment:
未來污水處理發(fā)展的五個趨勢：
1) nutrient removal and recovery,
營養(yǎng)鹽去除劑回收技術(shù)
2) trace organic compounds,
微量有機污染物；
3) energy conservation and production,
能量轉(zhuǎn)換和產(chǎn)生
4) sustainability, and
可持續(xù)性
5) community engagement.
公眾參與
The water industry has historically taken far longer than other business sectors to develop and implement new technologies. However, many innovations are now under development with benefits that could be compelling enough to shorten the length of the technology life cycle in the water sector. Implementation of these technologies would radically alter wastewater treatment plants in the future.
Current trends and highlights of some of today’s technical innovations, including nutrient removal and recovery, fine sieves, nitritation- Anammox processes, anaerobic treatment, sludge pre-treatment, and thermal conversions, are discussed.
Background
Speculation on the future of wastewater treatment continues to be a recurring theme in the water industry. Predictably, the future will be shaped by events that cannot be predicted and that will influence the future in ways that are impossible to foresee. However, studying the trends and forces shaping current events, and using this knowledge to develop possible boundaries for future conditions, can result in better insights into what might occur.
Strategic Planning
When the future is assumed to be like the past, forecasts can be made by simple, linear extrapolations. However, with greater degrees of uncertainty that conditions will continue as they are, forecasting becomes less useful. One structured method for evaluating these uncertainties is known as scenario planning, scenario thinking, or scenario analysis. With scenario planning, flexible plans for the future are prepared by evaluating alternative scenarios that could exist in the future. Future mapping is a more visually-based variation on scenario planning that attempts to examine a range of possible futures. Neither process attempts to predict the future, but rather develops an understanding of the forces and their relationships that could shape future conditions.
By creating several plausible, but distinctly different sets of future conditions, an organization can test the viability of current strategies under new circumstances. Ultimately, the goal is to be able to make better planning decisions that provide the flexibility to adapt to future changes.
Global Trends
Current trends (patterns of gradual change) often become the starting point for assessments of possible future conditions. Progressive changes in aspects of our society, businesses, and environment can be discerned and used to foresee the ultimate results of these changes over time. Past experience shows that most significant trends derive from underlying socio-cultural, economical, political, technical, ecological, demographic, organizational, and risk factors. Trends occur at all levels, with The largest, global changes affecting nearly everything, while localized trends will only affect specific regions, locations, or industries.
Key global trends with implications for the water industry include changes in population and demographics, increased urbanization, increasing living standards, climate change, and a scarcity of resources needed to sustain life, including land, water, and phosphorus. Regardless of the scale, utilities can benefit by being aware of the forces at work, and by being prepared to adapt to opportunities and threats that could significantly affect them.
A number of individuals and organizations have explored trends in the water industry including the Water Environment Research Foundation, or WERF (Crawford, G., 2010; Henderson, D., 2011), STOWA, the Dutch acronym for Stichting Toegepast Onderzoek Waterbeheer or Foundation for Applied Water Research (2010), the Water Research Foundation (Means, E.G., III et al., 2006), and the European Commission (Segrave, A. et al., 2007; Zuleeg, S. et al., 2006; and Rosén, L. and Lindhe–Chalmers, A., 2007). These different groups have expressed widely divergent views, as evidenced by the summary of selected studies in Table 1, although there is some commonality. Even though many of these studies were done within the context of potable water supplies, most of the identified trends apply equally to wastewater.
Wastewater Trends
From the perspective of the wastewater industry, five major trends, that encompass some of those in Table 1, are evident. These include nutrient removal and recovery, energy conservation and production, sustainability, treatment for non-traditional contaminants, and community engagement.
Nutrient Removal and Recovery – Nutrient removal to reduce nitrogen and phosphorous has been a reality in central Florida since the 1980s. In the future, nearly all treatment facilities will provide some nutrient reduction. Much of the near-term focus will be on meeting lower numeric limits; however, recovery and reuse of materials, initially phosphorus, will likely become mandatory at larger facilities over time. Taking a tiered approach to nutrient limits is likely the best long-term strategy, because the tiers allow flexibility to tailor effluent quality to a variety of reuse applications, thus providing the ability to maximize reuse while minimizing costs. One advantage to lower nutrient effluent limits is that treatment to meet lower effluent limits concentrates nutrients in the solids, where it may be more economical to recover and reuse Energy Management – Rising energy costs paired with restrictions on greenhouse gases will provide the impetus to institute more effective energy management and alternative energy strategies. These trends are raising the bar for wastewater utilities toward being energy neutral or energy positive, whereby energy is not just managed, but instead recovered and reused. Current initiatives to increase biogas production, manage oxygen demand, and control equipment for efficient power use will move the industry in the right direction. A fundamental change in the use of aerobic biological treatment may be required to complete the transition from energy user to energy supplier.
Future treatment plants may incorporate additional anaerobic processes, or chemical and physical barriers, to remove pollutants without aerobic bacteria thus creating energy rather than using energy. However, there are limits to the ability to increase the energy efficiency of existing processes, and there are budgetary limits for implementing new processes and technologies that help achieve an energy neutral target. A prudent strategy dictates that utilities work to achieve the energy neutral goal incrementally.
Toward that end, there are five key components that can frame energy optimization strategies including:
1) maximize efficiency;
2) provide more treatment for less power;
3) consider technologies to reduce or produce energy;
4) generate renewable power; and
5) evaluate the plant carbon footprint.
Sustainability – Better management of natural, human, social, manufactured, and intellectual capital to maintain a sustainable existence will become essential in the future. At wastewater treatment facilities, this will mean reduced consumption of resources and increased recycling and reuse of water, nutrients, and other materials contained in wastewater. In some areas, the need to increase reuse will require some decentralization with construction of satellite treatment plants. Caps on greenhouse gas emissions will affect the selection of treatment technologies and operating strategies particularly for sludge. Increased water conservation will alter both the flows and pollutant concentrations in raw wastewater, potentially leading to new challenges and opportunities.
Treatment for Non-Traditional Constituents – Public concerns over the presence of trace organic chemicals in water will accelerate the application of advanced treatment technologies to remove objectionable compounds from wastewater. Although there is reasonable certainty that removal of trace organic compounds will be needed, the timing, the specific compounds or classes of compounds that will require removal, and the technologies that will be needed, are unknown. Planning strategies might include leaving space on the plant site and in the hydraulic profile based on the technologies that we now know can remove some trace organics, including advanced oxidation processes and biological nutrient removal.
Community Engagement – The current trend for increased stakeholder involvement in utility decisions that affect neighbors of wastewater facilities or the cost of service should continue. Utilities can expect that their communities will demand to be part of the planning process for facility improvements, and that community enhancements be incorporated into utility projects.
Technical Innovations
The pace of innovation in the wastewater industry appears to be increasing, with every year bringing significant new concepts and technologies. Not all the technologies will succeed in the marketplace; however, some will. The following is a quick overview of a few promising wastewater treatment technologies that might be part of the treatment plant of the future.
Anaerobic Treatment – Anaerobic treatment of municipal wastewater is an attractive option for secondary wastewater treatment. The high costs of aeration and sludge handling associated with aerobic sewage treatment are dramatically lower with an anaerobic process as no oxygen is required for removal of carbonaceous oxygen demand and sludge production is reduced dramatically. Historically, however, anaerobic processes have not been feasible for carbonaceous BOD5 removal in municipal wastewater because of relatively low concentrations, the slow growth rate of anaerobic microbes, poor settleability of anaerobic sludge, and the potential for odors.
Phosphorus Recovery - Projections for the exhaustion of the world’s phosphorus reserves vary from less than 100 to over 300 years. More importantly; however, only eight countries contain over 90 percent of the known phosphate rock reserves, and just three (China, the United States, and Morocco/Western Sahara) have the bulk of the commercial reserves. Various predictions have the United States running out of phosphate rock within 25 to 30 years, although some of these predictions are at least that old. In some countries without phosphate rock reserves, the capture and recycling of phosphorus from wastewater has already become a major endeavor as a means to increase the security of their food supply.
Research into methods of recovering phosphorus from wastewater, originally initiated as a means for controlling magnesium ammonium phosphate (struvite), have accelerated over the last ten years. At present, the most feasible option is to precipitate struvite from side streams from dewatering anaerobically digested sludge. While side stream precipitation of struvite can recover about 40 percent of the influent phosphorus load, combining mainstream phosphorus removal with recovery from the sludge stream can capture up to 90 percent. Processes under development include additional precipitation methods, including one using a waste building material, and wet chemical and thermal methods for recovering phosphorus from sludge and incinerator ash. While phosphorus recovery and recycling may not be economical for some time, some are looking to the water industry to show the way, and to become an incubator for nutrient recovery technologies.
Nitrogen Cycle Revisited – Significant developments over the last 10 to 15 years have led to new processes for removing nitrogen from wastewater, particularly from warm, high-ammonia side streams from dewatering anaerobically digested sludge. Typical nitrogen removal at a wastewater treatment plant is a multi-step process in which a combination of autotrophic and heterotrophic bacteria sequentially converts ammonia to nitrogen gas. The classic nitrification- denitrification process can be managed so that the initial conversion of ammonia by ammonia oxidizing bacteria (AOBs) is stopped at nitrite (nitritation), and then the nitrite is converted to nitrogen gas (denitritation) by normal heterotrophic bacteria, thereby reducing the oxygen and carbon required for nitrogen removal. Coupling nitritation with denitritation provides a 25 percent savings in energy cost over conventional nitrification, and 40 percent savings in methanol cost over conventional denitrification.
Advances in molecular methods, aided by serendipity, have led to the discovery of microorganisms in both natural ecosystems and in biological treatment processes that were unknown less than 20 years ago. We now recognize that many more microorganisms are involved and their interactions are more complex. For example, both archaea and planctomycetes are major players in the nitrogen cycle of the open oceans; both microorganisms were unknown 20 years ago.
Ozone with Granular Activated Carbon (GAC) and Biological Aerated Filter (BAF) – 臭氧-粒狀活性炭聯(lián)用或曝氣生物濾池或許可以去除一些難以被活性污泥段去除的微量有機污染物
Conventional treatment does not provide effective removal for all trace organic contaminants (TOrCs), and advanced treatment may be required depending on the compound, concentration, and future regulations. While researchers have shown that ozonation provides excellent removal of numerous TorCs, no single treatment process is capable of removing all TorCs to below sensitive analytical detection limits (Benotti, M.J. et al., 2009; Snyder, S.A. et al., 2007). For example, fire retardants are one group of compounds that are not well removed by ozonation, but are well removed by GAC.
A plant of the future should include process flexibility to implement a multi-barrier approach for TorC removal, where additional advanced treatment processes, such as GAC or BAF, would provide TorC removal for compounds not well removed by ozonation alone.
Thermal Conversion – Recognizing the potential energy content of wastewater residuals, newer technologies are being developed to create energy independent systems. Gasification and pyrolysis are among the most promising of these technologies, which are being increasingly developed, both of which traditionally require sludge to be dried to 90 percent solids. Some new gasification developments appear to show promise at 50% solids or even 10% solids, thus eliminating the energy intensive drying stage. The gasification process heats solids to above 800 oC under oxygen-starved conditions to form syngas, which is mainly composed of hydrogen and carbon monoxide. The energy content of the syngas can be increased by adding steam to the process, a spin-off known as hydrogasification.
Pyrolysis creates syngas similar to gasification, but operates in the 700 oC range and in an oxygen-free environment. Both processes are designed as close-coupled systems, where the syngas is burned to heat flue gas, which is then used as the heat source for the drying process. In both cases, most of the recoverable energy is used to dry the solids, leaving little to produce power. As a result, many close-coupled systems are net-positive energy consumers.
The green energy and cleaner emission potential of gasification and pyrolysis are gaining momentum among alternative thermal treatment technologies. In a two-stage system, syngas can be conditioned for use in cogeneration systems to produce electricity. Newer systems are using the syngas to produce clean diesel or hydrogen. Alternative feedstocks, such as agriculture waste FOG, food waste, green waste, and wood waste, can increase the energy content of the syngas. Rather than using it to produce energy, syngas can be purified and injected into a natural gas grid or purified to create an alternative fuel commodity, essentially eliminating combustion and associated emissions.
美國著名Carollo 環(huán)境工程公司專家Rod Reardon 展望：污水處理當(dāng)前及未來發(fā)展趨勢
美國著名Carollo環(huán)境工程公司專家桿里爾登展望:污水處理當(dāng)前及未來發(fā)展趨勢
2014-08-11 Reardon 水進展
2014-08-11里爾登水進展
The wastewater industry faces many new challenges that complicate near- and long-term planning decisions. Increasing energy costs, trace organic compounds, finite resources, water conservation, and inexorably more stringent regulations, must all be considered before investing in major facility improvements. While the future is never certain, inclusion of strategic exercises like scenario planning and future mapping during the planning process can help to define the boundaries of what the future might bring to treatment facilities.
污水行業(yè)面臨著許多新的挑戰(zhàn),短期和長期的規(guī)劃決策復(fù)雜化。增加能源成本、微量有機化合物,有限的資源,節(jié)約用水,并無情地更嚴(yán)格的規(guī)定,之前都必須考慮投資主要設(shè)施的改進。未來從來都是不確定的,包含戰(zhàn)略演習(xí)情景規(guī)劃和未來在規(guī)劃過程中映射可以定義未來可能帶來的邊界處理設(shè)施。
Futurists point out that the important trends in the future have their seeds in the present. On this basis, treatment technologies will evolve to address five major trends in wastewater treatment:
未來學(xué)家指出,重要的趨勢在未來有自己的種子在當(dāng)下。在此基礎(chǔ)上,處理技術(shù)將在廢水處理解決五大發(fā)展趨勢:
未來污水處理發(fā)展的五個趨勢：
未來污水處理發(fā)展的五個趨勢:
1) nutrient removal and recovery,
1)營養(yǎng)物去除和恢復(fù),
營養(yǎng)鹽去除劑回收技術(shù)
營養(yǎng)鹽去除劑回收技術(shù)
2) trace organic compounds,
2)微量有機化合物,
微量有機污染物；
微量有機污染物;
3) energy conservation and production,
3)節(jié)能和生產(chǎn),
能量轉(zhuǎn)換和產(chǎn)生
能量轉(zhuǎn)換和產(chǎn)生
4) sustainability, and
4)可持續(xù)性,
可持續(xù)性
可持續(xù)性
5) community engagement.
5)社區(qū)的參與。
公眾參與
公眾參與
The water industry has historically taken far longer than other business sectors to develop and implement new technologies. However, many innovations are now under development with benefits that could be compelling enough to shorten the length of the technology life cycle in the water sector. Implementation of these technologies would radically alter wastewater treatment plants in the future.
供水行業(yè)歷史上已經(jīng)遠遠超過其他業(yè)務(wù)部門制定和實施新技術(shù)。然而,許多創(chuàng)新現(xiàn)在正在開發(fā)的好處,可以令人信服的足夠的長度縮短技術(shù)在水行業(yè)生命周期。實施這些技術(shù)將從根本上改變在未來污水處理廠。
Current trends and highlights of some of today’s technical innovations, including nutrient removal and recovery, fine sieves, nitritation- Anammox processes, anaerobic treatment, sludge pre-treatment, and thermal conversions, are discussed.
當(dāng)前的趨勢和突出的一些今天的技術(shù)創(chuàng)新,包括營養(yǎng)物去除和復(fù)蘇,細(xì)篩子,nitritation -氨氧化過程中,厭氧處理,污泥預(yù)處理、和熱轉(zhuǎn)換,進行了討論。
Background
背景
Speculation on the future of wastewater treatment continues to be a recurring theme in the water industry. Predictably, the future will be shaped by events that cannot be predicted and that will influence the future in ways that are impossible to foresee. However, studying the trends and forces shaping current events, and using this knowledge to develop possible boundaries for future conditions, can result in better insights into what might occur.
猜測的未來污水處理水行業(yè)仍然是一個反復(fù)出現(xiàn)的主題�？梢灶A(yù)見的是,未來將由無法預(yù)測的事件,這將影響未來的方式是無法預(yù)見的。然而,研究趨勢和力量塑造時事,和使用這些知識為未來開發(fā)可能的邊界條件,可以導(dǎo)致更好的見解可能發(fā)生什么。
Strategic Planning
戰(zhàn)略規(guī)劃
When the future is assumed to be like the past, forecasts can be made by simple, linear extrapolations. However, with greater degrees of uncertainty that conditions will continue as they are, forecasting becomes less useful. One structured method for evaluating these uncertainties is known as scenario planning, scenario thinking, or scenario analysis. With scenario planning, flexible plans for the future are prepared by evaluating alternative scenarios that could exist in the future. Future mapping is a more visually-based variation on scenario planning that attempts to examine a range of possible futures. Neither process attempts to predict the future, but rather develops an understanding of the forces and their relationships that could shape future conditions.
當(dāng)未來被認(rèn)為是像過去,預(yù)測可以通過簡單、線性推斷。然而,以更大程度的不確定性,條件將繼續(xù),預(yù)測變得不那么有用。一個結(jié)構(gòu)化的方法來評估這些不確定性被稱為情景規(guī)劃,場景中思考,或場景分析。情景規(guī)劃,靈活的未來計劃準(zhǔn)備通過評估選擇場景中可能存在的未來。未來的映射是一個更多的基于變化情景規(guī)劃,試圖檢查一系列可能的未來。無論是過程試圖預(yù)測未來,而是發(fā)展力量和它們之間的關(guān)系的理解,塑造未來的條件。
By creating several plausible, but distinctly different sets of future conditions, an organization can test the viability of current strategies under new circumstances. Ultimately, the goal is to be able to make better planning decisions that provide the flexibility to adapt to future changes.
通過創(chuàng)建一些似是而非,但未來截然不同的條件下,一個組織可以測試新形勢下當(dāng)前的可行性策略。最終的目標(biāo)是能夠做出更好的規(guī)劃決策,提供適應(yīng)未來變化的靈活性。
Global Trends
全球趨勢
Current trends (patterns of gradual change) often become the starting point for assessments of possible future conditions. Progressive changes in aspects of our society, businesses, and environment can be discerned and used to foresee the ultimate results of these changes over time. Past experience shows that most significant trends derive from underlying socio-cultural, economical, political, technical, ecological, demographic, organizational, and risk factors. Trends occur at all levels, with The largest, global changes affecting nearly everything, while localized trends will only affect specific regions, locations, or industries.
目前的趨勢(漸變的模式)往往成為未來可能的起點評估條件。我們的社會進步的變化方面,可以看出企業(yè)和環(huán)境和用于預(yù)測這些變化的最終結(jié)果。過去的經(jīng)驗表明,最重要的趨勢來自底層社會文化,經(jīng)濟、政治、技術(shù)、生態(tài)、人口、組織、和風(fēng)險因素。各級趨勢發(fā)生,最大、全球變化影響幾乎所有,而本地化趨勢只會影響特定區(qū)域,位置,或行業(yè)。
Key global trends with implications for the water industry include changes in population and demographics, increased urbanization, increasing living standards, climate change, and a scarcity of resources needed to sustain life, including land, water, and phosphorus. Regardless of the scale, utilities can benefit by being aware of the forces at work, and by being prepared to adapt to opportunities and threats that could significantly affect them.
關(guān)鍵全球趨勢與影響供水行業(yè)包括人口和人口結(jié)構(gòu)的變化、城市化增長,提高生活標(biāo)準(zhǔn),氣候變化,和稀缺的資源需要維持生命,包括土地、水和磷。無論規(guī)模、公用事業(yè)可以受益的意識到部隊工作,和被準(zhǔn)備適應(yīng)機會和威脅的效果,可以極大地影響他們。
A number of individuals and organizations have explored trends in the water industry including the Water Environment Research Foundation, or WERF (Crawford, G. , 2010; Henderson, D. , 2011), STOWA, the Dutch acronym for Stichting Toegepast Onderzoek Waterbeheer or Foundation for Applied Water Research (2010), the Water Research Foundation (Means, E.G. , III et al., 2006), and the European Commission (Segrave, A. et al., 2007; Zuleeg, S. et al., 2006; and Rosén, L. and Lindhe–Chalmers, A. , 2007). These different groups have expressed widely divergent views, as evidenced by the summary of selected studies in Table 1, although there is some commonality. Even though many of these studies were done within the context of potable water supplies, most of the identified trends apply equally to wastewater.
許多個人和組織探索水行業(yè)的趨勢包括水環(huán)境研究基金會,或·沃夫(克勞福德,G。,2010;亨德森,D。荷蘭的縮寫,2011),STOWA Stichting Toegepast Onderzoek Waterbeheer或應(yīng)用水研究基金會(2010),水研究基金會(手段,如第三,et al .,2006)和歐盟委員會(Segrave,A . et al .,2007;Zuleeg,s . et al .,2006;和羅森,l . Lindhe-Chalmers,。,2007)。這些不同的團體表達了大相徑庭的觀點,就是明證選定研究的總結(jié)在表1中,盡管有一些共性。盡管許多研究都是在飲用水供應(yīng)的背景下完成的,大部分的趨勢同樣適用于廢水。
Wastewater Trends
廢水的趨勢
From the perspective of the wastewater industry, five major trends, that encompass some of those in Table 1, are evident. These include nutrient removal and recovery, energy conservation and production, sustainability, treatment for non-traditional contaminants, and community engagement.
從污水行業(yè)的角度來看,五大趨勢,包含一些在表1中,是顯而易見的。這些包括營養(yǎng)物去除和回收、節(jié)能和生產(chǎn),可持續(xù)發(fā)展,治療非傳統(tǒng)污染物,和社區(qū)的參與。
Nutrient Removal and Recovery – Nutrient removal to reduce nitrogen and phosphorous has been a reality in central Florida since the 1980s. In the future, nearly all treatment facilities will provide some nutrient reduction. Much of the near-term focus will be on meeting lower numeric limits; however, recovery and reuse of materials, initially phosphorus, will likely become mandatory at larger facilities over time. Taking a tiered approach to nutrient limits is likely the best long-term strategy, because the tiers allow flexibility to tailor effluent quality to a variety of reuse applications, thus providing the ability to maximize reuse while minimizing costs. One advantage to lower nutrient effluent limits is that treatment to meet lower effluent limits concentrates nutrients in the solids, where it may be more economical to recover and reuse Energy Management – Rising energy costs paired with restrictions on greenhouse gases will provide the impetus to institute more effective energy management and alternative energy strategies. These trends are raising the bar for wastewater utilities toward being energy neutral or energy positive, whereby energy is not just managed, but instead recovered and reused. Current initiatives to increase biogas production, manage oxygen demand, and control equipment for efficient power use will move the industry in the right direction. A fundamental change in the use of aerobic biological treatment may be required to complete the transition from energy user to energy supplier.
營養(yǎng)物去除和回收,減少氮、磷營養(yǎng)物去除是一個現(xiàn)實自1980年代以來在佛羅里達州中部。在未來,幾乎所有處理設(shè)施將提供一些營養(yǎng)。近期會關(guān)注會議的降低數(shù)值限制;然而,復(fù)蘇和重用的材料,最初磷,將可能成為強制性更大的設(shè)施。采用分層方法營養(yǎng)限制可能是最好的長期策略,因為層允許靈活地調(diào)整污水質(zhì)量各種重用應(yīng)用程序,從而提供最大化的重用,同時最小化成本的能力。降低營養(yǎng)污水限制一個優(yōu)點是,治療達到降低廢水的限制集中在固體營養(yǎng),它可能更經(jīng)濟的恢復(fù)和重用能源管理,能源成本的上漲搭配限制溫室氣體動力研究所將提供更有效的能源管理和替代能源戰(zhàn)略。這些趨勢提高廢水的酒吧公用事業(yè)能源中性或積極,即能源不僅僅是管理,而是恢復(fù)和重用。目前的措施,以提高沼氣產(chǎn)量,有效管理需氧量和控制設(shè)備用電量將該行業(yè)在正確的方向上。根本變革的使用需氧生物處理可能需要從能源用戶能源供應(yīng)商完成轉(zhuǎn)變。
Future treatment plants may incorporate additional anaerobic processes, or chemical and physical barriers, to remove pollutants without aerobic bacteria thus creating energy rather than using energy. However, there are limits to the ability to increase the energy efficiency of existing processes, and there are budgetary limits for implementing new processes and technologies that help achieve an energy neutral target. A prudent strategy dictates that utilities work to achieve the energy neutral goal incrementally.
未來處理廠可能將額外的厭氧過程,或化學(xué)和物理障礙,去除污染物不需氧細(xì)菌創(chuàng)造能量,而不是使用能量。然而,有限制的能力增加現(xiàn)有流程的能源效率,并有預(yù)算限制實施新的流程和技術(shù),幫助實現(xiàn)能源中性目標(biāo)。謹(jǐn)慎的策略要求公用事業(yè)工作逐步實現(xiàn)能源中性目標(biāo)。
Toward that end, there are five key components that can frame energy optimization strategies including:
為此,有五個關(guān)鍵組件,這些組件可以幀能量優(yōu)化策略包括:
1) maximize efficiency;
1)效率最大化;
2) provide more treatment for less power;
2)提供更多的治療更少的權(quán)力;
3) consider technologies to reduce or produce energy;
3)考慮技術(shù)來減少或產(chǎn)生能量;
4) generate renewable power; and
4)生成可再生能源;和
5) evaluate the plant carbon footprint.
5)評價植物的碳足跡。
Sustainability – Better management of natural, human, social, manufactured, and intellectual capital to maintain a sustainable existence will become essential in the future. At wastewater treatment facilities, this will mean reduced consumption of resources and increased recycling and reuse of water, nutrients, and other materials contained in wastewater. In some areas, the need to increase reuse will require some decentralization with construction of satellite treatment plants. Caps on greenhouse gas emissions will affect the selection of treatment technologies and operating strategies particularly for sludge. Increased water conservation will alter both the flows and pollutant concentrations in raw wastewater, potentially leading to new challenges and opportunities.
可持續(xù)發(fā)展,更好的管理自然、人類、社會、生產(chǎn)、和知識資本保持可持續(xù)生存在未來將變得至關(guān)重要。在污水處理設(shè)施,這將意味著減少資源消耗和增加回收和重用的水,營養(yǎng)和廢水中包含的其他材料。在一些地區(qū),需要增加重用需要一些權(quán)力下放與衛(wèi)星處理廠建設(shè)。限制溫室氣體排放將會影響的選擇特別是對污泥處理技術(shù)和操作策略。提高節(jié)約用水將改變流和原始廢水中污染物濃度,可能導(dǎo)致新的挑戰(zhàn)和機遇。
Treatment for Non-Traditional Constituents – Public concerns over the presence of trace organic chemicals in water will accelerate the application of advanced treatment technologies to remove objectionable compounds from wastewater. Although there is reasonable certainty that removal of trace organic compounds will be needed, the timing, the specific compounds or classes of compounds that will require removal, and the technologies that will be needed, are unknown. Planning strategies might include leaving space on the plant site and in the hydraulic profile based on the technologies that we now know can remove some trace organics, including advanced oxidation processes and biological nutrient removal.
治療非傳統(tǒng)成分——公眾擔(dān)憂在水中微量有機化學(xué)物質(zhì)的存在會加速的應(yīng)用先進的化合物廢水處理技術(shù)去除令人討厭。雖然是合理確定需要去除微量有機化合物,時機,具體的化合物或化合物類需要刪除,和需要的技術(shù),是未知的。離開空間規(guī)劃策略可能包括廠址和水力分布基礎(chǔ)上的技術(shù),現(xiàn)在我們知道可以刪除一些微量有機物,包括先進的氧化過程和生物營養(yǎng)物去除。
Community Engagement – The current trend for increased stakeholder involvement in utility decisions that affect neighbors of wastewater facilities or the cost of service should continue. Utilities can expect that their communities will demand to be part of the planning process for facility improvements, and that community enhancements be incorporated into utility projects.
社區(qū)參與——當(dāng)前的趨勢增加利益相關(guān)者參與效用決策影響鄰居的廢水設(shè)施或服務(wù)的成本應(yīng)該繼續(xù)下去。公用事業(yè)可以期望他們的社區(qū)需求為設(shè)備改進規(guī)劃過程的一部分,社區(qū)增強被納入公用事業(yè)項目。
Technical Innovations
技術(shù)創(chuàng)新
The pace of innovation in the wastewater industry appears to be increasing, with every year bringing significant new concepts and technologies. Not all the technologies will succeed in the marketplace; however, some will. The following is a quick overview of a few promising wastewater treatment technologies that might be part of the treatment plant of the future.
污水行業(yè)創(chuàng)新的步伐似乎越來越多,每年都帶來了重要的新概念和技術(shù)。并不是所有的技術(shù)將在市場上取得成功,然而,有些人會。下面是一個快速概述幾個有前途的廢水處理技術(shù),可能未來的處理工廠的一部分。
Anaerobic Treatment – Anaerobic treatment of municipal wastewater is an attractive option for secondary wastewater treatment. The high costs of aeration and sludge handling associated with aerobic sewage treatment are dramatically lower with an anaerobic process as no oxygen is required for removal of carbonaceous oxygen demand and sludge production is reduced dramatically. Historically, however, anaerobic processes have not been feasible for carbonaceous BOD5 removal in municipal wastewater because of relatively low concentrations, the slow growth rate of anaerobic microbes, poor settleability of anaerobic sludge, and the potential for odors.
厭氧處理,厭氧處理的城市污水二級污水處理是一個有吸引力的選擇。曝氣的高成本和污泥處理與好氧污水處理顯著降低與一個厭氧過程不需要氧碳質(zhì)需氧量和污泥產(chǎn)量顯著降低。從歷史上看,然而,厭氧過程沒有可行的碳質(zhì)BOD5去除城市污水由于濃度相對較低,厭氧微生物的增長速度緩慢,厭氧污泥沉降性差,以及潛在的氣味。
Phosphorus Recovery - Projections for the exhaustion of the world’s phosphorus reserves vary from less than 100 to over 300 years. More importantly; however, only eight countries contain over 90 percent of the known phosphate rock reserves, and just three (China, the United States, and Morocco/Western Sahara) have the bulk of the commercial reserves. Various predictions have the United States running out of phosphate rock within 25 to 30 years, although some of these predictions are at least that old. In some countries without phosphate rock reserves, the capture and recycling of phosphorus from wastewater has already become a major endeavor as a means to increase the security of their food supply.
磷復(fù)蘇——世界磷儲量預(yù)測疲憊的變化從100年不到300多年。更重要的是,然而,只有8個國家包含超過90%的已知的磷礦儲量和三(中國、美國和摩洛哥/西撒哈拉)有大量的商業(yè)儲備。各種預(yù)測美國的磷礦在25到30年,盡管其中的一些預(yù)測至少老了。在一些國家沒有磷礦儲量,磷的捕獲和回收廢水已經(jīng)成為一個主要的努力作為一種手段,提高他們的食品供應(yīng)的安全。
Research into methods of recovering phosphorus from wastewater, originally initiated as a means for controlling magnesium ammonium phosphate (struvite), have accelerated over the last ten years. At present, the most feasible option is to precipitate struvite from side streams from dewatering anaerobically digested sludge. While side stream precipitation of struvite can recover about 40 percent of the influent phosphorus load, combining mainstream phosphorus removal with recovery from the sludge stream can capture up to 90 percent. Processes under development include additional precipitation methods, including one using a waste building material, and wet chemical and thermal methods for recovering phosphorus from sludge and incinerator ash. While phosphorus recovery and recycling may not be economical for some time, some are looking to the water industry to show the way, and to become an incubator for nutrient recovery technologies.
研究的方法從廢水回收磷,最初開始作為一種手段來控制磷酸鎂銨(鳥糞石),加速了在過去的十年。目前,最可行的選擇是鳥糞石沉淀從一邊流脫水污泥厭氧消化。雖然側(cè)流沉淀鳥糞石可以恢復(fù)約40%的磷負(fù)荷的影響,結(jié)合主流除磷和恢復(fù)從污泥流可以捕獲高達90%。流程正在開發(fā)包括額外的降水方法,其中包括使用建筑材料浪費,和濕化學(xué)和熱從污泥和垃圾焚燒廠灰回收磷的方法。雖然復(fù)蘇和磷回收可能不是經(jīng)濟在一段時間內(nèi),一些正在尋求水行業(yè)顯示方式,并成為營養(yǎng)恢復(fù)技術(shù)的孵化器。
Nitrogen Cycle Revisited – Significant developments over the last 10 to 15 years have led to new processes for removing nitrogen from wastewater, particularly from warm, high-ammonia side streams from dewatering anaerobically digested sludge. Typical nitrogen removal at a wastewater treatment plant is a multi-step process in which a combination of autotrophic and heterotrophic bacteria sequentially converts ammonia to nitrogen gas. The classic nitrification- denitrification process can be managed so that the initial conversion of ammonia by ammonia oxidizing bacteria (AOBs) is stopped at nitrite (nitritation), and then the nitrite is converted to nitrogen gas (denitritation) by normal heterotrophic bacteria, thereby reducing the oxygen and carbon required for nitrogen removal. Coupling nitritation with denitritation provides a 25 percent savings in energy cost over conventional nitrification, and 40 percent savings in methanol cost over conventional denitrification.
氮循環(huán)重新審視——重大進展在過去的10至15年導(dǎo)致氮從廢水中去除的新流程,尤其是來自溫暖,high-ammonia側(cè)流脫水污泥厭氧消化。典型的氮去除,污水處理廠是一個多步驟的過程中,自養(yǎng)和異養(yǎng)細(xì)菌順序?qū)钡獨怏w。經(jīng)典的硝化——反硝化過程可以管理的初始轉(zhuǎn)換氨,氨氧化細(xì)菌(aob)停在亞硝酸鹽(nitritation),然后是亞硝酸鹽轉(zhuǎn)化為氮氣(denitritation)正常的異養(yǎng)細(xì)菌,從而減少所需的氧氣和碳氮去除。耦合nitritation denitritation提供儲蓄25%的能源成本在傳統(tǒng)的硝化作用,傳統(tǒng)脫氮和40%的儲蓄在甲醇成本。
Advances in molecular methods, aided by serendipity, have led to the discovery of microorganisms in both natural ecosystems and in biological treatment processes that were unknown less than 20 years ago. We now recognize that many more microorganisms are involved and their interactions are more complex. For example, both archaea and planctomycetes are major players in the nitrogen cycle of the open oceans; both microorganisms were unknown 20 years ago.
分子方法的進步,得益于意外,導(dǎo)致微生物的發(fā)現(xiàn)在這兩個自然生態(tài)系統(tǒng)和生物處理過程中未知的不到20年前。我們現(xiàn)在認(rèn)識到,更多的涉及到微生物和它們的交互更加復(fù)雜。例如,古生菌和planctomycetes都是氮循環(huán)的主要參與者的開放海洋;20年前微生物都是未知的。
Ozone with Granular Activated Carbon (GAC) and Biological Aerated Filter (BAF) – 臭氧-粒狀活性炭聯(lián)用或曝氣生物濾池或許可以去除一些難以被活性污泥段去除的微量有機污染物
臭氧與顆粒活性炭(GAC)和曝氣生物濾池(BAF)——臭氧-粒狀活性炭聯(lián)用或曝氣生物濾池或許可以去除一些難以被活性污泥段去除的微量有機污染物
Conventional treatment does not provide effective removal for all trace organic contaminants (TOrCs), and advanced treatment may be required depending on the compound, concentration, and future regulations. While researchers have shown that ozonation provides excellent removal of numerous TorCs, no single treatment process is capable of removing all TorCs to below sensitive analytical detection limits (Benotti, M.J. et al., 2009; Snyder, S.A. et al., 2007). For example, fire retardants are one group of compounds that are not well removed by ozonation, but are well removed by GAC.
常規(guī)治療不提供有效的去除所有的微量有機污染物(金屬飾環(huán)),和先進的治療可能需要根據(jù)化合物,濃度,和未來的法規(guī)。雖然研究人員已經(jīng)表明,臭氧化提供了很好的去除許多金屬飾環(huán),沒有單一的處理過程能夠消除所有金屬飾環(huán)下面敏感的分析檢測的限制(Benotti,M.J. et al .,2009;斯奈德,S.A. et al .,2007)。例如,阻燃劑是一組化合物不是被臭氧化,但被廣汽。
A plant of the future should include process flexibility to implement a multi-barrier approach for TorC removal, where additional advanced treatment processes, such as GAC or BAF, would provide TorC removal for compounds not well removed by ozonation alone.
未來的植物應(yīng)該包括流程靈活性實現(xiàn)multi-barrier方法去除金屬飾環(huán)、額外的先進的處理工藝,如廣汽或BAF,提供除金屬飾環(huán)化合物不會被單獨臭氧化。
Thermal Conversion – Recognizing the potential energy content of wastewater residuals, newer technologies are being developed to create energy independent systems. Gasification and pyrolysis are among the most promising of these technologies, which are being increasingly developed, both of which traditionally require sludge to be dried to 90 percent solids. Some new gasification developments appear to show promise at 50% solids or even 10% solids, thus eliminating the energy intensive drying stage. The gasification process heats solids to above 800 oC under oxygen-starved conditions to form syngas, which is mainly composed of hydrogen and carbon monoxide. The energy content of the syngas can be increased by adding steam to the process, a spin-off known as hydrogasification.
熱轉(zhuǎn)換——認(rèn)識到廢水的潛在能量殘差,新技術(shù)正在開發(fā)創(chuàng)建能源獨立的系統(tǒng)。氣化和熱解是最有前途的技術(shù)之一,它正在日益發(fā)達,這兩個傳統(tǒng)需要干污泥固體的90%。一些新的氣化發(fā)展顯示承諾固體固體50%甚至50%,從而消除能源密集型干燥階段。氣化過程加熱固體高于800攝氏度在缺氧條件下形成合成氣,它主要由氫氣和一氧化碳。合成氣的能量通過添加蒸汽的過程中,可以增加一個稱為加氫氣化。
Pyrolysis creates syngas similar to gasification, but operates in the 700 oC range and in an oxygen-free environment. Both processes are designed as close-coupled systems, where the syngas is burned to heat flue gas, which is then used as the heat source for the drying process. In both cases, most of the recoverable energy is used to dry the solids, leaving little to produce power. As a result, many close-coupled systems are net-positive energy consumers.
熱解產(chǎn)生氣化合成氣相似,但在700 oC范圍和一個無氧的環(huán)境。兩個進程都設(shè)計成短背的系統(tǒng),合成氣燃燒熱煙氣,然后作為干燥過程的熱源。在這兩種情況下,大部分的可恢復(fù)的能量被用來干燥固體,離開產(chǎn)生電能。因此,許多短背的系統(tǒng)凈能源消費者。
The green energy and cleaner emission potential of gasification and pyrolysis are gaining momentum among alternative thermal treatment technologies. In a two-stage system, syngas can be conditioned for use in cogeneration systems to produce electricity. Newer systems are using the syngas to produce clean diesel or hydrogen. Alternative feedstocks, such as agriculture waste FOG, food waste, green waste, and wood waste, can increase the energy content of the syngas. Rather than using it to produce energy, syngas can be purified and injected into a natural gas grid or purified to create an alternative fuel commodity, essentially eliminating combustion and associated emissions.
綠色能源和清潔排放的潛力氣化和熱解替代熱處理技術(shù)中獲得動力。在一個兩級系統(tǒng)中,合成氣可以條件用于熱電聯(lián)產(chǎn)系統(tǒng)發(fā)電。新系統(tǒng)使用的是合成氣生產(chǎn)清潔柴油或氫氣。替代原料,如農(nóng)業(yè)廢物霧,糧食浪費,綠色廢物和木材廢料,可以提高合成氣的能量。而不是用它來產(chǎn)生能量,可以凈化合成氣和注入天然氣網(wǎng)格或純化創(chuàng)建一個替代燃料商品,基本上消除燃燒和排放有關(guān)。
